This application claims benefit of Japanese Patent Application No. 2001-029221 filed on Feb. 6, 2001, the contents of which are incorporated by the reference.
The present invention relates to portable telephone communication method and system and, more particularly, to portable telephone communication method and system capable of coping with a plurality of arrived calls at a time.
Portable telephone systems have been rapidly spread owing to their convenience merits, and the number of their sets having been spread is now exceeding the number of installed telephone sets or terminals. Also, the performance of portable telephone systems are becoming higher and higher, and portable telephone sets having new functions which are not provided in the installation type telephone sets have been developed. Prior art concerning installation type telephone sets is disclosed in, for instance, Japanese Patent Laid-Open No. 2000-224340 entitled “Portable Telephone Set with Recording Function” (hereinafter referred to as first prior art), Japanese Patent Laid-Open No. 9-139978 entitled “Voice Signal Transmitting and Receiving System” (hereinafter referred to as second prior art), Japanese Patent Laid-Open No. 10-200962 entitled “Multiple-Call Communication System: (hereinafter referred to as third prior art), Japanese Patent Laid-Open No. 11-150602 entitled “Radio Telephone System” (hereinafter referred to as fourth prior art) and Japanese Patent Laid-Open No. 11-177678 entitled “Message Recording and Reproducing System” (hereinafter referred to as fifth prior art).
The above first prior art concerns portable telephone sets with recording function, in which up and down voices can be sorted out for recording in an external recorder. The second prior art concerns portable telephone sets with recording function capable of hearing not only voice from the opposite side but also recorded voice during communication. The third prior art concerns systems, in which a time division multiplex communication path is established between a base station controller and a plurality of mobile terminals, whereby multiple call communication can be executed via a single mobile terminal. The fourth prior art concerns a radio telephone system, in which each mobile terminal can be simplified for connection with less incomprehensible channels when adding a voice recording function, and the user himself or herself can appropriately select the voice quality or the recording time by compressing the voice data and increasing the voice recording time when preserving more voice data. The fifth prior art concerns a message recording and reproducing system, in which the reproduction of messages having been sent out from recorded callers can be processed for each caller.
As shown above, the spread of the portable telephone, leads to increased occasions of communication between portable telephone sets or from other telephone sets and thus frequent cases of arrival of a new call during communication with a portable telephone set. In such cases of arrived call overlap, it has been inevitable to select either refusing the new call or answering the new call by interrupting the communication of the prevailing call. This means that such operations as interruption of communication and data transfer become necessary with respect to either one of the opposite side users, thus extremely spoiling the convenience of the portable telephone system.